Syrian activists say ISIL fighters have re-entered the historic city of Palmyra in central Syria.

The activist-run Palmyra Coordination Collective says the militants seized the city’s military warehouse and its northern and western neighborhoods after taking several government positions, oil fields, and strategic hilltops in the surrounding countryside in a lightning three-day assault.

It comes nine months after ISIL were expelled by Syrian and Russian forces in a highly publicized campaign.

The UK-based Syrian Observatory for Human Rights says the militants have reached the city’s Tadmor Hospital and its strategically located wheat silos.

The militants destroyed several of the city’s famed ancient Roman monuments and executed its archaeological director after sweeping into the city in July 2015 and holding it for 11 months.